Influence of context-sensitive urban and architectural design factors on the energy demand of buildings in Toulouse, France

Abstract

This research aims to identify the statistical sensitivity of multi-scale urban design factors regarding buildings’ energy demand located in three districts in the city of Toulouse, France. The research method is composed of four main steps: (a) three typical urban blocks of Toulouse are parametrized, considering factors ranging from the urban form to the building material scales; (b) a fractional factorial sampling method is applied which allows elaborating statistically representative and non-redundant scenarios from all design variables and for each specific urban district; (c) the urban energy models generated are interactively assessed regarding the annual buildings’ heating and cooling loads for the temperate climate context of Toulouse, France; (d) through a global sensitivity analysis, results obtained are estimated through a statistic hypothesis test, which allows identifying the influence of the design variables on each energy response of interest. Results show that urban multi-scale design variables may have divergent influence on the same energy response when the urban form context changes. For traditional urban compact blocks, two less current urban form factors considered in this study (the courtyard aspect ratio and the standard-deviation of the built height) account for almost 50% of the overall impact on heating demand of buildings while building and envelope scale factors, such as glazing window properties, have more influence for pavilions and slabs urban blocks. The relevance of certain factors was strongly linked to their typologies or to their urban environment.